Kevin ate 1 slice of cake. Gabriela ate 3 slices. If there were initially 7 slices, what fraction of the cake was eaten?
$\text{fraction of cake eaten} = \dfrac{\text{number of slices eaten}}{\text{number of slices total}}$ They ate ${4}$ out of $7$ slices. They ate $\dfrac{4}{7}$ of the cake.